SOUTH GATE (CBS)  —  Authorities put South Gate High School on lockdown for nearly three hours Friday after someone brandished a gun at a student outside the campus, officials said.

The student went inside the school and reported the incident around 3:40 p.m. and authorities were notified, said Susan Cox of the Los Angeles Unified School District.

Officers located and detained three suspects at Ardmore and Dearborn Avenues, Cox said.

It was unknown if any suspects were students at the school.

The school was no longer under protection by 6:30 p.m.

Classes were dismissed at 2:47 p.m., but around 200 students and faculty who had been involved in after school activities remained on the campus at the time of the incident, Cox said.

They were all safely located in a small gym and in surrounding classrooms, Cox said.

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